... 10 9 risk matrix, 10 6starting air manual control system FMECA, 11 1hazard and operability studies, 11 0 17 application example, 11 2 13 guide words, 11 2other applications, 11 3, 11 7piping and instrument ... failures, 210 13 failure statistics, 210 12 , 211 inspection intervals, 210 percentage distribution of root causes of failures, 211 risk ranking, 212 13 Pressure Systems Safety Regulations, 42–3, 10 0probability ... function, 16 9exponential failure, 17 2lognormal type, 17 1normal, 17 0normal distribution histogram, 17 6product risk assessment, 16 6–9design risk, 16 7–8design risk ranking, 16 7limiting risk, 16 8–9probability...